Rock Products Committee SCOPING DOCUMENT Increasing Crumb Rubber Usage Small Amount of CRM in Hot Mix Asphalt March 4, 2015

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1 SCOPING DOCUMENT Task Group Problem Process Annual Title by Using a Issue/Problem Statement Expedited Emerging Initiative Section of the Public Resources Code (AB 338) requires Caltrans to use a specific amount of crumb rubber modifier (CRM) in its asphalt paving materials. Increasing the alternatives available for using CRM in pavements is very desirable so that the amount of CRM used in asphalt paving materials can consistently meet or exceed the requirements established by the California legislature. One asphalt paving material where increasing CRM usage should be explored is hot mix asphalt Type A which typically accounts for at least 50 percent of all annual hot mix asphalt used on Caltrans projects. The Caltrans specifications currently do not allow even a small amount, between 5-10 percent by weight of asphalt binder, of CRM in Type A hot mix asphalt. Background California is faced with the challenge of diverting more than 40 million scrap tires from landfills annually in the state. The California Department of Resource Recycling and Recovery (CalRecycle) is responsible for finding new uses of waste tires. In 2010 CalRecycle estimated that of the approximately 41.1 million reusable waste tires generated in California, 33 million (81 percent) were diverted through various alternatives including reuse, retreading and combustion. In 2005, the Legislature passed and the governor signed AB 338, which requires Caltrans to use a specific percentage of CRM per metric ton of the total amount of asphalt paving materials it uses each year. Specifically, as of 2013, Caltrans is required to use, on an annual average, pounds of CRM per metric ton of the total amount of asphalt paving materials. In 2006 the Federal Highways Administration (FHWA) Recycled Materials Policy was established. The FHWA policy states the following: 1. Recycling and reuse can offer engineering, economic and environmental benefits. 2. Recycled materials should get first consideration in materials selection. Page 1 of 9

2 3. Determination of use of recycled materials should include an initial review of engineering and environmental suitability. 4. An assessment of economic benefit should follow in the selection process. 5. Restrictions that prohibit the use of recycled materials without technical basis should be removed from the specifications. Caltrans has recently changed its mission statement to include sustainability and to have the goal of Sustainability and Stewardship, which is to preserve and enhance California s resources and assets. It is time for an innovative approach for drastically increasing the amount of CRM used in California s pavements to support these environmentally related goals. Caltrans proposes to reduce landfill disposal of scrap tires by requiring that all hot mix asphalt contain a small amount of CRM. A small amount of CRM in hot mix asphalt is defined as either 5-10 percent by weight of asphalt binder or percent by weight of aggregate is used in hot mix asphalt. The proposed increased in the use of CRM is driven by environmental considerations and not enhanced performance. Purpose Increase the use of scrap tires so that the disposal of scrap tires in California landfills is eliminated and scrap tires are seen as a renewable resource rather than a waste product. The purpose of this RPC project is to identify, evaluate and implement additional alternatives to use a small amount of CRM in asphalt paving materials. A relatively small amount of CRM in hot mix asphalt is defined as either 5-10 percent by weight of asphalt binder or percent by weight of aggregate is used in hot mix asphalt. There are technical, environmental, economic, and performance issues that must be considered when a small amount of CRM is used in hot mix asphalt that this project will address. Objectives/Deliverables The objectives of this effort are to evaluate the advantages/disadvantages of the various alternatives in terms of the following factors: technical, environmental, economic and performance. The expected outcome is a variety of alternative approaches that will accommodate the addition of a small amount of CRM in hot mix asphalt, and allow Caltrans to meet the legislative requirements on CRM usage. Page 2 of 9

3 Caltrans and Industry have identified the following four alternatives that will accommodate the addition of a small amount of CRM in hot mix asphalt: 1. Caltrans PG+5 for unmodified binders meeting all current PG specification requirements 2. Caltrans PG+5 with changes to some requirements of the specification, e.g., solubility percent CRM per ton of HMA (~ 5-10 lb/ton HMA); i.e., dry process 4. Field blend 5-10 percent CRM (by weight of binder) The alternatives will be evaluated in four phases as follows: Phase 1: Laboratory Testing Phase 2: Field Evaluation of Pilot Projects Phase 3: Environmental and Life Cycle Cost Analysis Phase 4: Specification Development and Implementation The Objectives/Tasks and Deliverables required for the evaluation and implementation of each alternative will be based on available national information, including existing specifications. A work plan for each alternative will be developed by the Sub Task Group detailing the Objectives/Tasks, Deliverables, schedule and resources. The following table shows the Objectives/Tasks and Deliverables anticipated for the evaluation of the alternatives and will be used by the Sub Task Group as a template for developing the work plans. Objective/Task and Deliverable Phase Objective/Task Deliverable 1 Literature Search Literature summary based on a brief review of available literature. Work plan development A comprehensive, executable Experimental Design Strategy Evaluation Crumb Rubber Modified Materials Asphalt Binder Testing Asphalt Binder Quality Characteristic Requirements work plan A comprehensive, executable experimental design. Develop any required changes in test protocols necessary. Determine any modifications to the existing quality characteristic requirements for PG unmodified asphalt binders Targeted Completion Date 12/31/ /31/2015 3/30/2016 9/30/2016 9/30/2016 Page 3 of 9

4 Objective/Task and Deliverable Continued Phase Objective/Task Deliverable 1 Preliminary draft specification and test protocols Asphalt Binder Testing Hot Mix Asphalt Testing Draft specification and associated test protocols. Laboratory testing of asphalt binders for compliance with draft specification Laboratory testing of hot mix asphalt for compliance with hot mix asphalt quality characteristics based on the type of HMA Targeted Completion Date 9/30/ /30/ /30/ Field evaluations Pilot projects construction 7/31/2017 Evaluation of Asphalt Laboratory testing of asphalt 9/30/2017 Binder binders for compliance with Evaluation of hot mix asphalt on projects draft specification Laboratory testing of hot mix asphalt for compliance with hot mix asphalt quality characteristics Identification of construction issues Report on pilot projects construction issues. 3 Expected performance Evaluation of expected performance using CalME Life Cycle Cost Analysis Report comparing alternatives against existing paving materials. Life Cycle Analysis Environmental Benefits Report comparing alternatives against existing paving materials. Report comparing benefits, such as scrap tires diverted and reduced crude oil, for alternatives against existing paving materials. 9/30/ /30/2017 3/30/2017 Page 4 of 9

5 Phase Objective/Task 3 Green House Gas Impacts Emissions Impacts Objective/Task and Deliverable Continued Deliverable Report comparing alternatives against existing paving materials. Report comparing alternatives against existing paving materials. 4 Final Specification Finalize specification based on pilot projects results Specification implementation Post specification as either a Standard Special Provision (SSP) or Revised Standard Specification (RSS) Targeted Completion Date 12/30/2017 4/01/2018 Asphalt Binder COC Update COC Program 2/28/2018 Program Material Plant Quality If necessary, revise MPQP. 2/28/2018 Program Crumb Rubber If necessary, revise crumb 2/28/2018 Verification rubber verification forms. Guidelines Policy Bulletin 6/30/2018 (CPB) or Manual Update. Implementation support Technical support 6/30/2018 All alternatives will also be evaluated for the following: issues Industry impacts Timeline Activity for this project would begin in October Completion timelines are dependent upon the various alternatives, but likely a minimum of 3years is anticipated due to necessity of pilot projects to address any construction issues. Page 5 of 9

6 Benefits The following benefits are considered: Reduction of scrap tires in landfills Increased crumb rubber usage in pavement materials Potentially a reduction in greenhouse gases (crude oil) Potentially improved life cycle cost Impacts Compliance with legislative mandates. Materials and construction specifications will need to be modified. Positive or negative impact on stakeholders depending upon participation in the market. Resource Requirements The estimated Caltrans resource requirements and estimated research costs are shown are based on 4 alternatives. Caltrans Resource Requirements and Research Costs Phase Objective/Task Caltrans Staff Person Years (PY s) Research Estimated Cost (Dollars) 1 Literature Search Pavement 0.05 $20,000 Work Plan development Pavement; METS; 0.20 $5,000 Experimental Design Pavement; METS; 0.20 $5,000 development Asphalt Binder Quality Pavement; METS; 0.30 $5,000 Characteristic Requirements Preliminary draft Pavement; METS; 0.10 $5,000 specification and test protocols Asphalt Binder Testing Pavement; METS; 0.3 $90,000 Hot Mix Asphalt Testing METS 0.3 $200,000 Page 6 of 9

7 Phase Objective/Task Caltrans Resource Requirements and Research Costs Caltrans Staff Person Years (PY s) Research Estimated Cost (Dollars) 2 Plan field evaluations Pavement; METS; Evaluation of Asphalt METS Binder Evaluation of hot mix METS asphalt on projects. Identification of Pavement; METS; construction issues 3 Expected Performance Pavement; 0.05 $55,000 Life Cycle Cost Analysis Pavement; 0.10 $40,000 Life Cycle Analysis Pavement; 0.10 $35,000 Environmental Benefits Pavement; 0.05 Included in Life Cycle Green House Gas Impacts Pavement; 0.05 Included in Life Cycle Emissions Impacts Pavement; 0.05 Included in Life Cycle Page 7 of 9

8 Phase Objective/Task Caltrans Resource Requirements and Research Costs Caltrans Staff 4 Final specification Pavement; METS;, Office Engineer Specification Pavement; implementation Asphalt Binder COC Pavement; METS, Program Material Plant Quality Pavement; Program, Crumb Rubber Pavement; Verification Person Years (PY s) Research Estimated Cost (Dollars) 0.30 $5, $15, N/A 0.05 N/A 0.05 N/A Guidelines 0.10 N/A Implementation support Pavements, 0.10 $25,000 Research Reports Technical Memoranda 0.10 $45,000 and reports Totals: 3.50 $550,000 To support this research UCPRC request the following testing equipment be purchased: Dynamic Shear Rheometer (DSR) used to characterize the viscous and elastic behavior of asphalt binders. The total research costs for this project is $635,000. Caltrans is partnering with CalReycle on this projects and it is estimated that CalRecycle will fund approximately $390,000 of the $550,000 or 71 percent of the research costs excluding equipment purchased. Impediments to Completion of Deliverables Caltrans Districts and Industry resistance to change Caltrans resources personnel and financial Available research resources Page 8 of 9

9 Recommendation and Approval This scoping document for by using Small Amount of CRM in Hot Mix Asphalt was prepared by the to address a priority issue that has statewide significance to both Caltrans and Industry. It is within the Rock Products Committee mission. The Task Group Co-Chairs have determined the scope, resources required and timeline for delivery of this project to ensure that the deliverables are achievable in a timely manner. Recommended for Approval by: m Greutert Caltrans Task Group Co-Chair Sri Balasubramanian Caltrans Task Group Co-Chair Caltrans Task Group Co-Chair Approved by: Jesse Bhullar Caltrans RPC Co-Chair Phil Stolarski Caltrans RPC Co-Chair Approval Date: 1 o lcr I 1s-, I Page 9 of9